@mixin bg-image($url){
	background-image: url($url+'@2x.png');
	@media(-webkit-min-device-pixel-ratio:3),(min-device-pixel-ratio:3){
		background-image: url($url+'@3x.png');
	}
}
@mixin border-1px($color) {
	position: relative;
	&::after{
		display: block;
		position: absolute;
		left: 0;
		bottom: 0;
		content: '';
		width: 100%;
		border-top: 1px solid $color;
	}
}
@mixin border-none() {
	&::after{
		display: none;
	}
}